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Join award winning teacher Jonathan Bergmann as he interactively teaches Astronomy: Solving the Problem of Astronomical Motion. Astronomers of antiquity did not connect gravity and astronomical motion. Galileo investigated this connection with exper...iments using projectiles and balls rolling down planks. Galileo put science on course to determine laws of motion and to develop the scientific method. After this introduction, the concept of gravity is explained and demonstrated. Newton's theories on the motion of the moon are also explained. ( 9:14)[more]

Copernicus was ridiculed by his peers and Galileo was found guilty of heresy by the Catholic church for their views that the Sun (not the Earth) was the center of the Solar System. The video has a fascinating account of Galileo's observations of Venu...s. Run time 05:06.[more]

The telescope forever changed astronomy by providing more detailed views of distant objects than was previously possible. Galileo pioneered astronomy as the first person to study the celestial objects through a telescope. His observations, including ...the discovery of moons around Jupiter, helped revolutionize the way people thought about the universe. This video segment adapted from NOVA describes some of Galileo's first discoveries with the telescope. Closed captioning included. Run time 03:04.[more]

Before the 17th century, people generally believed that Earth was at the center of the universe. Galileo, however, was not afraid to challenge existing beliefs when he published his work in support of the Sun-centered, or heliocentric, Copernican the...ory. In this video segment adapted from NOVA, learn about the two opposing worldviews and the strong piece of evidence Galileo offered to support the heliocentric theory. Closed captioning included. Run time 05:06.[more]

Galileo used thought experiments to test many assumptions, including the notion that heavy objects fall more quickly than lighter objects when they are dropped. Lacking access to either a vacuum chamber or a planetary body that has no atmosphere, he ...nevertheless correctly predicted that all falling objects would accelerate at the same rate in the absence of air resistance. In this video segment from NASA, astronaut David Scott demonstrates the correctness of Galileo's prediction. Run time 0:47.[more]

Galileo used his telescope to gather data about the heavens, and his observations and theories sparked much controversy. Contrary to the popular belief of the time, Galileo suggested that Earth was not the center of the universe. In this video segmen...t adapted from NOVA, the importance of unbiased scientific inquiry is demonstrated by Galileo's observations of sunspots. Closed captioning included. Run time 03:42.[more]

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